Method and apparatus for lining a closure



Dec. 30, 1969 .A. PODESTA ETAL 3,486,959

METHOD AND APPARATUS FOR LINING A CLOSURE Filed Jan. 19, 1966 i 2 Sheets-Sheet 1 FIG. 3

I INVENTQR$ CARLO Mam/4T7 ANDRE BE/PEZ/Ah A RAM/v00 P0059771 Dec. 30, A. PODESTA ETAL METHOD AND APPARATUS FOR LINING A "CLOSURE Filed Jan. 19, 1966 2 Sheets-Sheet 2 L EA u I l\\ \l r. \m 17/ 1s/18/ United States Patent Int. Cl. 1332b 31/00 US. Cl. 156262 9 Claims ABSTRACT OF THE DISCLOSURE An apparatus and method for the insertion of a sealing blank into a cap for effecting a lateral seal and a plane seal in which the cap has a flat central body portion, a skirt portion depending from the outer edges of the body portion and a curvilinear rim on the end of the skirt. the sealing blank being shaped to correspond with the shape of the cap and dimensioned to be larger in cross-section than the body portion of the cap with concentric slits separating the blank into a central body portion and an outer disc portion with ram means for displacement of the blank into the cap whereby the skirt portion separates from the central body portion to deposit the skirt portion on the skirt and the central body portion onto the body portion of the cap.

This invention relates to a closure for use in effecting a sealing relationship with the neck of a container and it relates more particularly to a cap or closure embodying such sealing means and to a method and apparatus for the production of same.

The closure of this invention is adapted for use with a container or bottle having a neck with a beaded portion at its outer edge in which the summit of the curvature at the outer edge lies in a flat plane. For engagement with the neck of the container for closure thereof, there is provided a cap generally formed with a central body portion that spans the space between the summit edge and is tangent thereto and a skirt portion which extends downwardly from the edge of the body portion adjacent the lateral edge of the bead, when in the assembled relation, and which terminates in an inturned or outturned lower lip which operates to effect a latching engagement with the undesirable of the bead, when in the assembled relation. The cap is provided with sealing means in its inner portions for effecting a fluid-tight seal between the beaded portion of the container and the closure.

It is desirable to provide a means for effecting a sealing relationship between the lateral skirt portion of the cap and the beaded portion of the container. It is also desirable to line the body portion of the cap with a sealing member to prevent fluid in the container from coming into contact with metal portions of the closure or cap.

Thus it is an object of this invention to produce and to provide a method and means for producing a cap embodying sealing means whereby a fluid-tight seal is effected when the cap is mounted in position of use on the container; which embodies a lateral seal for effecting a sealing relationship between the skirt of the cap and the lateral portions of the neck ring or bead, and which embodies a lining seal for sealing the mouth of the container and to prevent fluid from coming into contact with metal portions of the closure; in which the dual sealing effects can be secured in a'single operation; in which use is made of a single blank of sealing material which separates during installation to give the desired dual seal effect; which makes use of a single die punch system for the insertion of the sealing blank into the cap or closure separately to "ice locate the portions of the sealing member in the desired locations within the closure, and in which the method and means are efficient and simple in operation and use to enable quick and inexpensive fabrication of a cap with a minimum amount of labor and equipment.

These and other objects and advantages of this invention will hereinafter appear and for purposes of illustration, but not of limitation, an embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 is a sectional elevational view of the neck portion of a bottle or container showing the beaded mouth;

FIG. 2 is a top plan view of the neck portion of the container shown in FIG. 1;

FIG. 3 is a top plan View of a strip of sealing material showing the sealing blank cut out for insertion into the closure;

FIG. 4 is a schematic sectional elevational view showing the relative positions of the parts at the initial stages for insertion of the sealing blank into a formed closure;

FIG. 5 is a schematic sectional elevational view similar to that of FIG. 4 showing the parts in their relative positions upon completion of the operation for inserting the sealing blank into the closure; and

FIG. 6 is a sectional elevational view showing a more sophisticated mechanism for the insertion of the sealing blank into the closure.

The advantages of having both a lateral seal and an annular fluid-tight seal are well recognized, The closure may be positive in nature, that is to say that it has a shape and form whereby any effort tending to tear the closure from the container will tend to effect further compression of the seal thereby to enhance the fluid-tightness. On the other hand, with reference to the flat annular seal, any etfort which tends to tear the cap from the bottle will reduce the compression of the lateral seal and relax the fluid-tightness. However, the flat annular seal operates to provide the desired sealing relationship to prevent contact between the metal portions of the closure and the fluid within the container. Thus there is a desire to make simultaneous use both of the seal to provide fluid-tightness and the seal to protect the content material from contact with the metal closure.

To achieve these results, it has been necessary separately to manufacture and properly to locate the two sealing members and it has not heretofore been possible to achieve these operations in a manner sufliciently economical for use with such very low cost closures. The desired sealing effect has been made possible by the method and means of this invention wherein a Single sealing blank is prepared for insertion in a single sealing operation to give the desired arrangement of dual sealing elements within the closure.

As illustrated in FIGS. 1 and 2, the typical neck 1 of a bottle is formed with a ring or bead b at the mouth having a summit curve 3 at the outer edge in which the tangent thereto lies in the flat plane indicated by the broken lines 2. When the neck of the bottle is round, the summit curve 3 will define a circle; however, the invention is not limited to round necks but can be adapted as well to containers having necks of different shapes such as of elliptical shape, and the like.

The invention will be described with reference to a container having a neck of rounded shape and a closure member formed of sheet metal having a central body portion dimensioned to have a radius as great as, if not slightly greater than, the radius of the circle formed by the summit curve 3, a skirt of substantially S-shape depending from the edge of the body portion, and a curvilinear inturned lip at the lower edge of the skirt in position to eiiect locking engagement with the underside of the bead at the mouth of the container when the closure is applied in position of use on the container.

The sealing members are provided in the closure in two stages including a first stage addressed to the preparation of a sealing blank and a second stage addressed to the insertion of the blank into the closure including the separation thereof into two parts, one of which forms the lateral seal and the remainder of which forms the plane seal lining the body portion of the closure.

The sealing blank is cut from a thin strip of a suitable flexible sealing material with inner cuts or slits 11, 12 and 13 arranged about an arc of a circle having a radius which is slightly greater than the radius of the circle formed by the summit curve but in which the slits are unconnected one to the other to provide narrow intervening sections 14, 15 and 16 which serve temporarily to hold the central portion 17 in the blank. It is desirable to make use of at least three slits, as illustrated in FIG. 3, although more arcuate slits may be cut with intervening connecting zones, without departing from the spirit of the invention.

The sealing blank is cut out along the line 19 which defines a circle concentric with the slits 11, 12 and 13 but having a radius which is 1.1 to 2 times the radius of the summit curve and preferably within the range of 1.25 to 1.6 times the radius of the summit curve to provide an outer disc section 18 connected to the central section 17 by the portions 14, 15 and 16 between the slits. The sealing blank can be cut out from the strip in a single step as by means of a cutout punch. When the head of the container has a shape other than round, the slits and cutouts will correspond to the shape of the summit curve of the head but of the increased dimension in the proportions previously described for the circular neck.

In assembly, the cutout sealing blank is inserted into the molded cap 4 by means of a pusher member 20 having a rim portion in the form of a straight cylindrical section having a base of curvilinear cross-section intermediate the summit curve 3 of the container and the curve formed by the slits 11, 12 and 13.

When the rim is displaced in the direction towards the base of the cap, while the latter is at rest on the support 21, the sealing blank is engaged by the rim and is displaced therewith downwardly into the cap. The frictional resistance operates to tear or otherwise separate the central portion 17 from the outer portion 18 whereby the rim continues to displace the central portion 17 downwardly against the flat body portion 5 of the cap while the outer disc portion 18 is pushed outwardly by the rim against the lateral skirt portion 6 of the cap.

In the preferred practice, use is made of a sealing material formed of a thermoplastic substance and heat is applied to raise the sealing material to a temperature within the range of 50100 0, depending somewhat upon the material used to reduce the sealing material to an adhesive stage for bonding the sealing member to the metal cap.

For this purpose, the sealing member is formed of plastic material such as a film or foil of polyvinyl chloride, polyethylene, polypropylene, polyamide, polytetrafluoroethylene, or a laminate of paper and plastic foil or a latex coated paper. It is preferred to make use of polyethylene because of its desirable physical properties and low cost and because it readily adheres to the metal of which the cap is formed when heated to an elevated temperature such as 70 C. The thickness of the foil of plastic material can be varied over a fairly wide range but it is preferred to make use of a strip of foil having a thickness within the range of 0.1 to 1 mm. and preferably of the order of about .3 mm.

In the modification illustrated in FIG. 6, use is made of a guide socket 40 having an internal bore dimensioned to correspond with the dimension and shape of the cap and having an annular flanged portion 42 which extends curvilinearly inwardly from the side wall to define an opening therebetween corresponding to the crosssectional dimension of the portion of the cap between the locking lip sections. The portion of the guide socket beneath the flanged section 42 comprises a bottom housing 41 in which the cap 4 is inserted with the locking end lips underlying the flanges 42 as the cap rests with its base on the support 30.

The sealing blank 17 is inserted into the upper portion of the bore above the flanged portion 42.

Shiftable endwise into the bore of the guide socket is a ram 50 having a head 51 with a plurality of elongate resilient fingers 52 depending therefrom as spaced tongues having a lower curvilinear outer edge and which together define a cylindrical section concentric with the periphery of the bore. As the ram is displaced downwardly through the bore of the guide socket, the fingers 52 slide along the inside wall of the socket for displacement of the inserted sealing blank into the cap upon engagement therewith. As the fingers are displaced onto the flanged portions 42 they are cammed inwardly in the direction towards each other and as the sealing blank 17 penetrates the narrowest portion of the socket member between flange members 42, it is separated into the two parts 17 and 18. The central portion 17 is displaced downwardly by the ends of the fingers onto the base portion 5 of the cap while the lateral disc portion 18 of the sealing member slides off to the outside of the fingers and is pressed against the lateral skirt portion 6 of the cap.

The ram can be modified to include a flat central hammer (not shown) within the area defined by the spring fingers and which is dimensioned to have a length to extend for a distance equal to the spring fingers and preferably slightly beyond the ends thereof to engage the central portion 17 of the sealing member and which operates strongly to press the central portion 17 of the sealing blank against the body portion of the cap 4 to eflect a bonded relationship. It is desirable to again make use of heat suflicient to enhance softening of the thermoplastic material for improving the bonded relation.

It will be apparent from the foregoing that there is provided a new and improved method for the production of a metal cap closure having dual sealing members wherein the desired sealing effect is secured from a single blank in a single stroke of assembly.

It will be understood that changes may be made in the details of construction, arrangement and operation without departing from the spirit of the invention.

We claim:

1. In the method of producing a cap for closure of the neck of a container having a rounded lip at the mouth thereof which defines a summit curve in a flat plane and in which the cap has a flat central body portion shaped to correspond to the summit curve and dimensioned to be slightly greater in cross-section than the summit curve, a skirt portion depending from the edge of the body portion and a curvilinear rim on the end of the skirt adapted to effect latching engagement with the underside of the lip when the cap is in position of use as a closure, the improvement comprising providing a sealing blank from a strip of sealing material in which the blank is shaped to correspond to the summit curve and dimensioned to have a cross-section 1.1 to 2 times larger than the cross-sectional dimensions of the summit curve and a series of slits spaced inwardly from the edge but spaced outwardly of the outline of the summit curve to subdivide the sealing blank into a central body portion and an outer disc portion with the slits being unconnected one with the other to provide an intermediate section interconnecting the outer disc portion with the central body portion, and ramming the sealing blank into the cap with a ram having a base corresponding in shape to the summit curve and dimensioned to have a cross-section between the summit curve and the curve defined by the slits whereby, as the sealing blank is displaced by the ram into the cap, the body portion separates from the disc portion for displacement by the ram onto the underside of the body portion of the cap as a sealing lining while the disc portion is displaced outwardly into engagement with the lateral skirt.

2. The method as claimed in claim 1 in which the sealing blank is formed of a heat softenable plastic ma terial.

3. The method as claimed in claim 2 which includes the step of heating the plastic material to a temperature within the range of 50100 C. when rammed into the cap.

4. The method as claimed in claim 1 in which the sealing blank is dimensioned to have a cross-section which is 1.25 to 1.6 times the cross-sectional dimensions of the summit curve.

5. The method as claimed in claim 1 in which, when the summit curve is circular, the sealing blank is of circular shape having a radius which is 1.1 to 2 times the radius of the summit curve and in which the slits define a circle having a radius less than the radius of the sealing blank but slightly greater than the radius of the summit curve.

6. The method as claimed in claim 1 in which the sealing blank has a thickness within the range of .1 to 1 mm.

7. An apparatus for the insertion of a sealing blank into a cap for effecting a lateral seal and a plane seal in which the cap has a flat central body portion, a skirt portion depending from the outer edges of the body portion and a curvilinear rim on the end of the skirt and in which the sealing blank is shaped to correspond to the shape of the closure and dimensioned to be larger in cross-section than the cross-sectional dimensions of the body portion of the closure with at least three slits spaced inwardly from the edge of the blank concentrically therewith to subdivide the sealing blank into a central body portion and an outer disc portion with the slits being unconnected one with the other to provide narrow sections in between which hold the disc and body portions together, said apparatus comprising a support on which the cap rests, a punch formed of -a head section and a plurality of elongate resilient strips depending from the head section in a pattern corresponding to the shape of the sealing blank and positioned to engage the sealing blank within the area between the slitted portion and the outer edge portion of the sealing blank and mounted for displacement in a direction toward and away from the support for engagement with the sealing blank for displacement thereof into the cap whereby, when the sealing blank enters the cap, the forces operate to separate the disc portion from the body portion for continued displacement of the body portion onto the underside of the body portion of the cap as a sealing lining and for displacemnt of the disc portion outwardly against the skirt for a lateral seal, a guide socket dimensioned to receive the cap therein with the inner surfaces of the guide socket in position to be engaged by the resilient strips of the punch for guiding the resilient strips into and out of the cap during movement of the punch in the direction toward and away from the support.

8. An apparatus as claimed in claim 7 in which the guide socket includes a portion which extends curvilinearly inwardly to define a narrow zone above the punch in which the cap is received.

9. An apparatus as claimed in claim 7 in which the punch includes in addition to the head and resilient strips, a central ram dimensioned to have a length at least as great as the resilient strips for engagement with the central portion of the sealing blank to press said central portion against the central body portion of the cap.

References Cited UNITED STATES PATENTS 2,910,397 10/1959 Husum et a1. 156-262 EARL M. BERGERT, Primary Examiner JOSEPH C. GIL, Assistant Examiner US. Cl. X.R. 

